Sondra Osterman was the third witness since the defense began its case Friday to testify that Zimmerman is screaming for help on the 911 call moments before he fatally shot Martin.
After the call was played for Sondra Osterman in the courtroom, defense attorney Mark O'Mara asked who it was.
"Yes, definitely. It's Georgie," said Sondra Osterman, who testified she first met Zimmerman in 2006 while working with him at a mortgage company.
The 911 call captured the confrontation between Zimmerman and Martin shortly before Zimmerman fatally shot the teen. Zimmerman's mother and uncle testified last Friday it was Zimmerman screaming. Martin's mother and brother also took the witness stand last Friday to say the voice belongs to Martin. The 911 call is a crucial bit of evidence and has been played for jurors repeatedly because it could determine who the aggressor was in the confrontation last year.
Zimmerman, a former neighborhood watch volunteer, has pleaded not guilty to second-degree murder and says he shot Martin in self-defense during a scuffle in the townhome complex where he lived. Martin was there visiting his father and his father's fiancee.
Prosecutors contend that Zimmerman was profiling Martin and perceived the teen as someone suspicious in the neighborhood, which had been the site of a series of break-ins.
Under cross-examination, prosecutor Bernie de la Rionda implied that Sondra Osterman and her husband, Mark, had a stake in the outcome of the trial because they had written a book about Zimmerman's case and were donating the proceeds to their friend. Mark Osterman took the witness stand after his wife to testify about how Zimmerman had purchased his firearm.
The prosecutor also played for Sondra Osterman a nonemergency police call Zimmerman made to report Martin walking through his neighborhood. In the call, Zimmerman uses the words, "F------ punks. These a-------. They always get away." Sondra Osterman identified the voice as Zimmerman's.
When asked by O'Mara if she detected ill will, spite or hatred in his voice, she answered no.
Prosecutors must show that Zimmerman acted with ill will, spite or a depraved mind in order to get a second-degree murder conviction.
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Copyright 2013 The Associated Press.